Spiny bivalve from Upper Triassic limestone at Aust Cliff, Gloucestershire, UK

[Georyx]

Hi everyone,

 

First time posting here so please forgive any dodgy formatting. I found this bivalve shell in the Upper Triassic limestone beds at Aust Cliff, Gloucestershire, UK.

 

I posted this on Reddit and only one person managed to have a guess at a Ctenostreon bivalve genus, but they are not sure. The spines on the edge of the shell seem a bit too evenly-spaced out in my opinion.

 

(By the way, the grooves surrounding the shell are from where I've engraved the fossil a little. I don't have the equipment to fully extract it, so I have no idea what the outside of the shell looks like).

 

Thanks all - any help would be appreciated.

- Georyx

[Tidgy's Dad]

I think Oxytoma sp. 

See here :